Display panel

Abstract

This invention provides a display panel comprising a display substrate, a reflective structure, a plurality of micro-light-emitting components, a plurality of refractive structures, and a light-transmitting structure. The reflective structure is disposed on the display substrate and divides the surface of the display substrate into a plurality of pixel regions. Each micro-light-emitting component is disposed in one of these pixel regions and has an upper surface on the side away from the display substrate, the upper surface defining a central region and a peripheral region surrounding the central region. Each refractive structure covers the peripheral region of one of the micro-light-emitting components and exposes the central region of the micro-light-emitting component therein, forming a notch. The light-transmitting structure covers the refractive structures and the micro-light-emitting components, filling each notch and contacting each central region, and the refractive index of the light-transmitting structure is less than the refractive index of the refractive structure. The display panel of this invention has better light extraction efficiency and can emit light uniformly.

Description

Technical Field

[0001] This invention relates to a display panel, and more particularly to a display panel with better light emission efficiency and uniform light emission. Background Technology

[0002] In current display panels, the light-emitting components (such as LED chips) are covered by an encapsulating colloid. Since the refractive index of the light-emitting component is greater than that of the encapsulating colloid, the surface of the light-emitting component is usually roughened to reduce the occurrence of total internal reflection. The roughening process makes the light emission angle of the light-emitting component more uniform, which means that some large-angle light rays will still undergo total internal reflection when they leave the light-emitting component and re-enter the encapsulating material or air interface.

[0003] The common solution is to place a lens above the light-emitting component to converge the light. However, the process of placing the lens encounters many challenges (such as placement failure or lens offset relative to the light-emitting component), resulting in limited light convergence effect of the lens or inconsistent convergence effect between individual pixels. This may lead to uneven light output from the display panel and low light output efficiency. Summary of the Invention

[0004] The present invention provides a display panel that has better light emission efficiency and can emit light uniformly.

[0005] A display panel of the present invention includes a display substrate, a reflective structure, a plurality of micro-light-emitting components, a plurality of refractive structures, and a light-transmitting structure. The reflective structure is disposed on the display substrate and divides the surface of the display substrate into a plurality of pixel regions. Each micro-light-emitting component is disposed in one of these pixel regions, and each micro-light-emitting component has an upper surface on a side away from the display substrate, the upper surface defining a central region and a peripheral region surrounding the central region. Each refractive structure covers the peripheral region of one of the micro-light-emitting components and exposes the central region of the micro-light-emitting component therein, forming a notch. The light-transmitting structure covers the refractive structures and the micro-light-emitting components, the light-transmitting structure fills each notch and contacts each central region, and the refractive index of the light-transmitting structure is less than the refractive index of the refractive structure. Each refractive structure has a contact surface on a side away from the corresponding peripheral region that contacts the light-transmitting structure, and each contact surface forms an acute angle with the upper surface of the corresponding micro-light-emitting component.

[0006] Based on the above, the notch design of the refractive structure of the display panel of the present invention allows light emitted from the central region of the micro-light-emitting components with a small divergence angle to not enter the refractive structure, thus avoiding the problem of light with a small divergence angle being refracted by the refractive structure and diverging. Furthermore, the notch design of the refractive structure allows light with a large divergence angle in the central region to enter the refractive structure, causing the light to undergo secondary refraction before reaching the reflective structure. This reduces the height at which the light is incident on the reflective structure, thereby reducing the need for the reflective structure. Additionally, the light reflected by the reflective structure can be directed towards the front of the micro-light-emitting components, improving light extraction efficiency. Since the light extraction efficiency of each micro-light-emitting component in the display panel is effectively improved, the light extraction uniformity of the display panel is increased. Attached Figure Description

[0007] Figure 1 This is a partial top view schematic diagram of a display panel according to an embodiment of the present invention;

[0008] Figure 2A It is along Figure 1 A cross-sectional view of line segment AA;

[0009] Figure 2B yes Figure 2A A schematic diagram of one type of light path;

[0010] Figure 2C yes Figure 2A A magnified view of a portion of the image;

[0011] Figure 3A This is a partial cross-sectional schematic diagram of a display panel according to another embodiment of the present invention;

[0012] Figure 3B and Figure 3C This is a partial cross-sectional schematic diagram of various refractive structures according to another embodiment of the present invention;

[0013] Figure 4A This is a partial cross-sectional schematic diagram of a display panel according to another embodiment of the present invention;

[0014] Figure 4B yes Figure 4A A schematic diagram of the light path of contact surfaces with different curvatures in the refractive structure;

[0015] Figure 5 This is a partial cross-sectional schematic diagram of a display panel according to another embodiment of the present invention.

[0016] Explanation of reference numerals in the attached figures

[0017] θ, θ1, θ2: included angles;

[0018] X1, X2, X3: Central axis;

[0019] B: Boundary line;

[0020] C: Angle threshold line;

[0021] L1~L17: Light rays;

[0022] 100, 100a, 100b, 100c: Display panels;

[0023] 110: Display substrate;

[0024] 112: Pixel area;

[0025] 120: Reflective structure;

[0026] 122: Reflecting wall;

[0027] 124: Lower part;

[0028] 126: Upper part;

[0029] 130: Miniature light-emitting component;

[0030] 132: Upper surface;

[0031] 134: Central area;

[0032] 136: Outer area;

[0033] 138: Emissive layer;

[0034] 140, 140b: Refractive structure;

[0035] 142: Notch;

[0036] 144, 144': Contact surfaces;

[0037] 145: Boundary point;

[0038] 146: Top;

[0039] 148, 148a, 148b, 148c: Inner sidewall;

[0040] 150: Transparent structure. Detailed Implementation

[0041] Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same component reference numerals are used in the drawings and description to denote the same or similar parts.

[0042] Figure 1 This is a partial top view of a display panel according to an embodiment of the present invention. Figure 2A It is along Figure 1A cross-sectional diagram of line segment AA. It should be noted that, for the sake of simplicity, Figure 1 The refractive structure 140 and the light-transmitting structure 150 are omitted. Figure 2A Only one micro-light-emitting component 130 and its corresponding structure are shown, but Figure 1 Other micro-light-emitting components 130 and their corresponding structures can also be as follows: Figure 2A As shown.

[0043] Please see Figure 1 and Figure 2A The display panel 100 in this embodiment includes a display substrate 110, a reflective structure 120, a plurality of micro light-emitting components 130, and a plurality of refractive structures 140. Figure 2A ) and light-transmitting structure 150 ( Figure 2A A reflective structure 120 is disposed on the display substrate 110. For example... Figure 1 As shown, the reflective structure 120 divides the surface of the display substrate 110 into multiple pixel regions 112. Each micro-light-emitting component 130 is disposed in one of these pixel regions 112.

[0044] In this embodiment, the reflective structure 120 may surround, for example, three micro-light-emitting components 130 simultaneously, but this is not a limitation. Furthermore, the micro-light-emitting components 130 may be, for example, micro-light-emitting diodes, but the type of micro-light-emitting components 130 is not limited thereto.

[0045] like Figure 2A As shown, the micro-light-emitting component 130 has an upper surface 132 on the side away from the display substrate 110. The upper surface 132 defines a central region 134 and a peripheral region 136 surrounding the central region 134. A refractive structure 140 covers the peripheral region 136 of one of these micro-light-emitting components 130, and the refractive structure 140 exposes the central region 134 of the micro-light-emitting component 130 to form a notch 142.

[0046] In this embodiment, the extent of the peripheral region 136 of the upper surface 132 is determined by the position of the refractive structure 140. That is, the area covered by the refractive structure 140 is the peripheral region 136, and the uncovered area is the central region 134. Of course, the definition of the extent of the peripheral region 136 is not limited to this. For example, the peripheral region 136 can refer to the area covered by the projection of the refractive structure 140 onto the upper surface 132, and is not necessarily the area that actually contacts and covers the upper surface 132.

[0047] like Figure 2A As shown, the refractive structure 140 in this embodiment is positioned relative to the central axis X1 of the micro-light-emitting component 130. Figure 2AThe curved structure is higher at the top and lower at the bottom. These refractive structures 140 are respectively filled between the corresponding micro light-emitting components 130 and the reflective structure 120, and between the micro light-emitting components 130 and the display substrate 110.

[0048] The refractive structure 140 has a contact surface 144 on the side away from the corresponding peripheral region 136, which contacts the light-transmitting structure 150, and each contact surface 144 forms an acute angle (angle θ) with the upper surface 132 of the micro-light-emitting component 130. Specifically, the side away from the peripheral region 136 refers to the upper surface (or outer surface) of the refractive structure 140 that contacts the light-transmitting structure 150 and forms an acute angle (angle θ) with the upper surface 132 of the micro-light-emitting component 130.

[0049] Furthermore, in this embodiment, the acute angle (angle θ) refers to the angle between the tangent at the intersection point 145 of the contact surface 144 and the reflective structure 120 and the extended surface of the upper surface 132, or the angle θ between the tangent of the contact surface 144 at the intersection point 145 and the plane parallel to the upper surface 132.

[0050] The refractive structure 140 may be a light guide structure made of a high-refractive-index photoresist, but is not limited thereto. The refractive structure 140 may be fabricated by first creating a contact surface 144 (e.g., an arc-shaped surface or a multi-segmented beveled surface) through the hydrophilic / hydrophobic properties of the material, or by means of reflow, inkjet printing (IJP), and then the center may be hollowed out by etching to form a notch 142.

[0051] Furthermore, the light-transmitting structure 150 covers the refractive structure 140 and the micro-light-emitting component 130. The light-transmitting structure 150 fills the notch 142 and contacts the central region 134, and the refractive index of the light-transmitting structure 150 is less than that of the refractive structure 140. In this embodiment, the light-transmitting structure 150 is, for example, an encapsulating colloid. Additionally, on the longitudinal section of the micro-light-emitting component 130, a portion of the light-transmitting structure 150 is disposed between these contact surfaces 144 and the reflective structure 120.

[0052] like Figure 2AAs shown, the notch 142 of the refractive structure 140 exposes the central region 134 of the micro-light-emitting component 130. Because the angle (divergence angle) between the light ray L1 emitted from the central region 134 of the micro-light-emitting component 130 and the vertical line is very small, the light ray L1 can directly exit upwards towards the micro-light-emitting component 130 without entering the refractive structure 140. Therefore, the display panel 100 avoids the problem of light ray L1 with a very small divergence angle being refracted by the refractive structure 140 and then diverging. Furthermore, compared to the prior art design that uses a full-surface coverage of the refractive structure 140, for light ray L1 with the same divergence angle in the central region 134, the notch 142 configuration in this embodiment reduces the difference in refractive index when the light path is refracted into the air (i.e., the refractive structure 140 with a higher refractive index is transformed into a lower refractive index light-transmitting structure 150). Therefore, when viewed from outside the display panel 100 (on the air side) towards the micro-light-emitting component 130, the central region 134 of this embodiment can receive more light at the same light-receiving angle.

[0053] For the light ray L2 with a small divergence angle emitted from the outer region 136, the light ray L2 will be refracted a second time at the contact surface 144 and then emitted upwards towards the micro light-emitting component 130.

[0054] In this embodiment, the reflective structure 120 has a reflective wall 122 on one side adjacent to each micro-light-emitting component 130. The reflective wall 122 includes a lower portion 124 and an upper portion 126. The lower portion 124 is connected to the display substrate 110. The upper portion 126 is connected to the lower portion 124, and the absolute value of the slope of the upper portion 126 relative to the upper surface 132 is less than the absolute value of the slope of the lower portion 124 relative to the upper surface 132. For the large divergence angle light L3 emitted from the central region 134, the light L3 can enter the refractive structure 140 and, after secondary refraction, reach the upper portion 126 of the reflective structure 120, and finally reflect upwards to improve the light emission efficiency of the display panel 100.

[0055] Furthermore, in this embodiment, the edge of the contact surface 144 of the refractive structure 140 is connected to the reflective structure 120. In this embodiment, on the longitudinal section of the micro-light-emitting component 130, the junction (intersection point 145) between the contact surface 144 and the reflective structure 120 is flush with or slightly higher than the upper surface 132 of the micro-light-emitting component 130, that is, located on the side of the upper surface 132 away from the display substrate 110.

[0056] The refractive structure 140 has a top 146 away from the upper surface 132, and each contact surface 144 includes a continuous curved surface, multiple curved surfaces with different curvature centers, or multiple inclined surfaces with different slopes in the direction of the top 146 toward the reflective structure 120.

[0057] It is worth mentioning that the reflective structures currently used in display panels mostly employ black matrix (BM) or more expensive white bank structures to prevent crosstalk between pixels. However, due to the limitation on the penetration depth of the photoresist during the exposure of the yellow light in the reflective structure manufacturing process, increasing the height of the reflective structure 120 would significantly reduce the process yield. In this embodiment, since the light L3 is refracted downwards at the contact surface 144, the incident height of the reflective structure 120 is lowered, thereby reducing the height requirement of the reflective structure 120. In other words, the display panel 100 can effectively reduce the height requirement of the reflective structure 120 through the arrangement of the refractive structure 140 and the design of the contact surface 144, thereby improving the yield of the exposure process.

[0058] Reference first Figure 2C In this embodiment, the absolute value of the tangent slope of the contact surface 144 relative to the upper surface 132 increases from the side adjacent to the notch 142 toward the side adjacent to the reflective structure 120.

[0059] Taking the contact surface 144 on the left as an example, the absolute value of the tangent slope is from... Figure 2C The slope increases from right to left. In other words, the slope of the tangent at the left contact surface 144 increases towards... Figure 2C The slope is steeper to the left (at the junction of the contact surface 144 and the reflective structure 120) and gentler to the right (top 146). Of course, the change in the tangent slope of the contact surface 144 is not limited by this.

[0060] The slope of the tangent of the contact surface 144 relative to the upper surface 132 varies, which can automatically homogenize the refraction effect of light. Specifically, the refractive structure 140 also has an inner wall 148 connected to the upper surface 132. Given that light in the central region 134 enters the refractive structure 140, when the divergence angle decreases, the incident angle of light entering the refractive structure 140 from the inner wall 148 is magnified, which increases the refraction angle of light after incident on the inner wall 148, resulting in an unfavorable increase in the incident position of secondary refraction within the refractive structure 140 (i.e., the contact surface 144).

[0061] Therefore, the design of the tangent slope of the contact surface 144 relative to the upper surface 132 gradually decreasing towards the top 146 allows for the automatic amplification of the incident angle of the light's second refraction within the refractive structure 140 as the incident point of the light enters the refractive structure 140. In other words, according to Snell's Law, since the sine function has the characteristic that the larger the incident angle, the greater the increase in the exit angle, the above design can effectively increase the degree of light deflection when exiting the refractive structure 140, thereby increasing the probability of the light being reflected by the reflecting structure 120.

[0062] Figure 2B yes Figure 2A A schematic diagram of one type of light path. Please refer to... Figure 2B It should be noted that, in Figure 2B In the diagram, solid ray L4 represents the path of light refracted by refractive structure 140, while dashed ray L5 represents the original light path without refractive structure 140. Here, rays L4 and L5 are drawn with refractive indices of 1.5 and 1.7 for the light-transmitting structure 150 and refractive structure 140, respectively. Rays L4 and L5 are emitted from the same position, and both have an angle θ1 (divergence angle) of 42 degrees with the vertical axis when they leave the upper surface 132 of the micro-light-emitting component 130. Simulation calculations show that after secondary refraction by refractive structure 140, solid ray L4 has an angle θ2 of 53 degrees with the vertical axis. Compared to ray L5 without refractive structure 140, ray L4 is deflected by 11 degrees. In other words, compared to ray L5, the incident position of ray L4 at the upper layer 126 can be reduced by 7.8%, achieving the aforementioned purpose of reducing the height of reflective structure 120.

[0063] In addition, for rays with a divergence angle (angle θ1) smaller than ray L5, these rays will have a larger incident angle when incident on the inner wall 148 and the contact surface 144. As described above regarding the sine function, these rays will also experience a more significant refraction effect on the contact surface 144 while their incident angle is magnified. Therefore, the design of the notch 142 of the refractive structure 140, combined with the slope variation of the contact surface 144, not only reduces the height requirement of the reflective structure 120, but also has the effect of converging the landing points of rays with different divergence angles into a smaller area, thereby simplifying the design of the shape of the upper part 126.

[0064] In this embodiment, the inner sidewall 148 is, for example, a vertical plane, but in other embodiments, for example... Figure 3B and Figure 3C The inner sidewall 148b shown may also include at least one plane, a curved surface, or a combination thereof. Furthermore, the display panel 100 can adjust the height of the reflective structure 120 by adjusting the area ratio of the peripheral region 136 covered by the refractive structure 140 to the upper surface 132.

[0065] If the notch 142 of the refractive structure 140 is narrower, that is, the proportion of the area of ​​the outer region 136 covered by the refractive structure 140 to the area of ​​the upper surface 132 is larger, in terms of light L4, it means that the inner wall 148 moves closer to the center, and the incident height of light L4 entering the inner wall surface 148 is lower, which can reduce the height requirement of the reflective structure 120.

[0066] On the other hand, the narrower the notch 142 of the refractive structure 140, the more light will enter the refractive structure 140. Since the light in the central region undergoes secondary refraction upon entering the refractive structure 140, the angle between the light leaving the refractive structure 140 and the vertical line becomes larger. Therefore, the height requirement of the reflective structure 120 can be reduced.

[0067] In this embodiment, the peripheral region 136 covered by the refractive structure 140 accounts for more than 50% of the area of ​​the upper surface 132, for example, 50% to 80%, but is not limited thereto. Changing the value of the area ratio of the peripheral region 136 covered by the refractive structure 140 to the upper surface 132 can affect the path of light rays with different divergence angles.

[0068] Figure 2C yes Figure 2A A magnified view of a portion of the image. Please refer to [link / reference]. Figure 2C For light rays emitted from the outer region 136 covered by the refractive structure 140, the dashed boundary line B is the boundary line where the light rays diverge or converge. If the light ray exits the refractive structure 140 along the boundary line B, it will exit in a straight line without deflection. Ray L6 is located to the right of the boundary line B (that is, the divergence angle of ray L6 is smaller). After being refracted once by the refractive structure 140, it is emitted upwards, and the ray L6 leaving the refractive structure 140 is located to the right of the boundary line B.

[0069] Ray L7 is located to the left of boundary line B (meaning ray L7 has a large divergence angle). After being refracted once by the refractive structure 140, it is directed toward the reflective structure 120 and reflected to the upper right. In other words, the large-angle ray L7 emitted from the outer region 136, after passing through the refractive structure 140 and being reflected by the reflective structure 120, will bend toward the center and converge toward the center.

[0070] For light ray L8 that is not covered by the refractive structure 140, originates from the central region 134 and has a large divergence angle, light ray L8 will be refracted twice by the refractive structure 140, and after being reflected by the reflective structure 120, it will be deflected towards the center and converge towards the center.

[0071] Compared to light ray L7, light ray L9 has a smaller divergence angle (the angle between it and the vertical line) when it leaves the upper surface 132. However, the angle at which light ray L9 is deflected to the upper right after being reflected by the reflective structure 120 is larger than the angle at which light ray L7 is deflected to the upper right. In other words, the angle between light ray L9 and the vertical line at the point where it is reflected by the reflective structure 120 increases, and it is located to the right of the angle threshold line C. Furthermore, the direction of light ray L9 will cross the center of the micro-light-emitting component 130 and exhibit a divergent light form.

[0072] The deflection modes of light rays L6 and L9 are explained separately below. For light ray L6 located to the right of the dividing line B, since the refractive structure 140 recedes from the center of the micro-light-emitting component 130 toward the reflective structure 120 to form a notch 142, when light ray L6 is incident on the contact surface 144, most of it will be located to the left of the normal. That is, the outgoing light of light ray L6 will be deflected toward the center of the micro-light-emitting component 130. In other words, the presence of the notch 142 makes it possible to minimize the divergence caused by light ray L6, which has a very small divergence angle and is directly incident from the outer region 136 onto the contact surface 144, being located to the right of the normal. More specifically, the above situation will only occur in a small area near the top 146 to the right of the dividing line B, but will not continue to occur in the area of ​​the notch 142. In this way, the display panel 100 can avoid the defect in the prior art where the encapsulating colloid is plano-convex, resulting in insufficient single deflection and causing the light to diverge more when leaving the convex side of the encapsulating colloid.

[0073] In the light beam L9, the boundary between the upper layer 126 and the lower layer 124 can be determined by the angle threshold line C after light reflection. Specifically, the angle threshold line C represents the critical line at which light, after being reflected by the reflective structure 120, crosses the center of the micro-light-emitting component 130. Therefore, the display panel 100 can adjust the position of the boundary between the upper layer 126 and the lower layer 124, for example, by lowering the boundary, so that light beam L9 can be reflected by the gently sloping upper layer 126. This reduces the deflection angle of light beam L9, allowing it to emit light more upwards and increasing light emission efficiency. Therefore, the designer can determine the position of the boundary between the upper layer 126 and the lower layer 124 by first selecting the angle threshold line C.

[0074] exist Figure 2C As can be seen, whether it is light L6 from the outer region 136 with a small divergence angle, light L7 from the outer region 136 with a large divergence angle, or light L8 from the central region 134 with a large divergence angle, the light path can be changed by the refractive structure 140, or by the refractive structure 140 and the reflection structure 120, so as to meet the requirement of small-angle light output.

[0075] Figure 3A This is a partial cross-sectional schematic diagram of a display panel according to another embodiment of the present invention. Please refer to... Figure 3A , Figure 3A and Figure 2A The main difference is Figure 3A The shape of the inner wall 148a is different Figure 2AThe inner sidewall 148. In this embodiment, the inner sidewall 148a of the refractive structure 140 is an upwardly inclined surface. The angle of inclination of the inclined surface relative to the upper surface 132 is, for example, 45° or more, but is not limited thereto.

[0076] The beveled design of the inner wall 148a can significantly deflect the incident normal of light rays entering the refractive structure 140. For light rays L10 with a large divergence angle emanating from the central region 134, the beveled design of the inner wall 148a can reduce the height of the incident point of light ray L10, thereby reducing the height of the subsequent refraction point.

[0077] Specifically, because the refractive index of the light-transmitting structure 150 is lower than that of the refractive structure 140, total internal reflection will not occur even if the incident angle of light L10 at the inner sidewall 148a is amplified. Furthermore, the inclined design of the inner sidewall 148a, compared to the vertical plane of the inner sidewall 148, allows light to travel further within the refractive structure 140. This significantly shortens the distance between the exit point of light L10 at the contact surface 144 and the reflective structure 120, thereby suppressing light divergence. Further, due to the difference in refractive index, light L10 can be refracted towards the display substrate 110 at the contact surface 144, directly reducing the height requirement of the reflective structure 120.

[0078] Figure 3B and Figure 3C This is a partial cross-sectional schematic diagram of various refractive structures according to another embodiment of the present invention. It should be noted that... Figure 3B and Figure 3C Only a partial refractive structure 140 is shown schematically, and other structures are hidden.

[0079] Please refer to the following first. Figure 3B , Figure 3B and Figure 3A The main difference is that, Figure 3B and Figure 3A The main difference is Figure 3B The shape of the inner wall 148b is different Figure 3A The inner sidewall 148a.

[0080] In this embodiment, the inner sidewall 148b of the refractive structure 140 includes a curved surface. In the direction from the top 146 toward the upper surface 132 (i.e.... Figure 3B Below the top surface 132, the absolute value of the slope of the tangent line of the inner wall 148b relative to the upper surface 132 increases from the top 146 towards the +X direction (that is, the slope of the inner wall 148 on the left increases towards the +X direction). Figure 3C (The lower part increases). In this embodiment, in the case of... Figure 3B In the direction from above to below, the trend of the tangent slope of the inner sidewall 148b is opposite to that of the trend of the tangent slope of the contact surface 144.

[0081] exist Figure 3B In the diagram, the solid line portion of ray L11 represents the path of ray L11 refracted when the inner wall 148b is a curved surface, and the dashed line portion represents the path of ray L11 refracted when the inner wall 148a is an inclined surface. Similarly, the solid line portion of ray L12 represents the path of ray L12 refracted when the inner wall 148b is a curved surface, and the dashed line portion represents the path of ray L12 refracted when the inner wall 148a is an inclined surface.

[0082] Comparing the solid and dashed portions of ray L11 with those of ray L12, it can be seen that for rays with the same divergence angle, due to the difference between the curved and inclined surfaces of the inner wall 148b, when the inner wall 148b is curved, the ray deflects at the normal to the incident surface of the refractive structure 140, resulting in smaller incident and exit angles. This further extends the optical path, causing the ray to exit the refractive structure 140 at a lower position, thereby reducing the reflection of the structure 120. Figure 3A (High demand)

[0083] Please see Figure 3C , Figure 3C and Figure 2A The main difference is that, in this embodiment, the inner wall 148c of the refractive structure 140 includes a curved surface. Similarly, the inner wall 148c of this embodiment, compared to... Figure 2A The vertical plane of the inner sidewall 148 can also achieve the above-mentioned effect.

[0084] Figure 4A This is a partial cross-sectional schematic diagram of a display panel according to another embodiment of the present invention. Please refer to... Figure 4A , Figure 4A The display panel 100b and Figure 2A The main difference in the display panel 100 is the shape of the refractive structure 140b.

[0085] In this embodiment, the refractive structure 140b is located near the central axis of the micro-light-emitting component 130 (e.g., Figure 2A The height of the refractive structure 140b is lower at the point of reflection and higher near the reflective structure 120. Furthermore, the height of the refractive structure 140b may be equal to or lower than the height of the reflective structure 120.

[0086] like Figure 4A As shown, the refractive structure 140b covers a portion of the surface of the reflective structure 120. Here, the design of this embodiment differs from the aforementioned... Figure 2A or Figure 3AIn this case, light only undergoes its first refraction at the contact surface 144 after being reflected by the reflective structure 120. That is to say, light leaving from the peripheral region 136 is mainly transmitted to the reflective structure 120 inside the refractive structure 140b through the mechanism of total internal reflection.

[0087] In this embodiment, these refractive structures 140b are in a direction perpendicular to the display substrate 110 ( Figure 4A The thickness (in the vertical direction) increases from the side adjacent to the notch 142 toward the side adjacent to the reflective structure 120. Furthermore, the absolute value of the tangent slope of the contact surface 144 relative to the upper surface 132 decreases from the side adjacent to the notch 142 toward the side adjacent to the reflective structure 120 (that is, the tangent slope of the left contact surface 144 decreases as it approaches the upper surface 132). Figure 4A (The less on the left).

[0088] For light rays L13 and L14 with large divergence angles (e.g., above 60 degrees) in the peripheral region 136 of the micro-light-emitting component 130, the design of such a refractive structure 140b can achieve a light pattern optimization effect. Specifically, by using the shape design of a concave or convex lens (or other polygonal prism) and utilizing the principle of total internal reflection, the light rays L13 and L14 with large divergence angles in the peripheral region 136 of the micro-light-emitting component 130 are guided by the refractive structure 140b to a very small area of ​​the reflective structure 120 (near the top 146 of the refractive structure 140b). Then, the reflective structure 120 (which can have a single slope, but is not limited to this) can guide these light rays L13 and L14 in similar directions and emit light upwards.

[0089] Furthermore, since the refractive index of the micro light-emitting component 130 is generally greater than that of the material of the common refractive structure 140b, the proportion of light rays L15 emitted from the peripheral region 136 with a small divergence angle is low. Moreover, since the incident angle of such light rays L15 to the contact surface 144 is small, the degree of divergence after being refracted by the refractive structure 140b is also slight, and the impact on the light output efficiency is not significant.

[0090] In addition, with Figure 2A , Figures 3A to 3C Compared to the refractive structure 140b in the other embodiment, which guides large diverging angle light rays from the central region to converge on the central axis, the refractive structure 140b in this embodiment hardly deflects or interferes with the light rays from the central region 134. In other words, the optical effect of this embodiment mainly lies in converging the diverging light lost in the peripheral region 136, and making the visual brightness change of the display panel 100b more smooth under different viewing angles. In other words, Figure 2A , Figure 3A and Figure 4A Both exhibit good light extraction efficiency; the main difference lies in their design approach.

[0091] Figure 4B yes Figure 4A A schematic diagram comparing the light paths of contact surfaces with different curvatures in the refractive structure. Please refer to... Figure 4B If the contact surface 144' is a portion of a perfect circle (such as a quarter arc), then the ray L16 at the critical angle will be guided along the tangent of the arc to the reflecting structure 120. Figure 4A ).

[0092] Figure 4B Lieutenant General Figure 4A The contact surface 144 is represented by a dashed line. The slope of the tangent to the contact surface 144 gradually decreases towards the top, causing the normal of the incident ray L17 at the contact surface 144 of the refractive structure 140b to deflect counterclockwise more significantly. As explained above, due to the refractive index factors between the materials, the light rays incident on the peripheral region 136 typically have a large divergence angle. Assuming... Figure 4B If the light ray L17 undergoes total internal reflection at the first incident position, the second and third segments of the reflected light ray also have a high probability of undergoing total internal reflection again. In detail, since the tangent slope of the contact surface 144 decreases to the left at a faster rate than that of a perfect circle (i.e., contact surface 144'), meaning that the contact surface 144 has a lower surface position, this ensures that the light ray L17 is re-incident at the contact surface 144, thus allowing it to be transmitted multiple times within the refractive structure 140b.

[0093] For light rays emanating from the outer region 136 and satisfying the condition of total internal reflection (such as light ray L17), the gradual decrease in the tangent slope also causes a reduction in the incident angle of the reflected light. Therefore, to ensure that subsequent incident angles are greater than or equal to the critical angle, there is an upper limit to the rate at which the tangent slope of the contact surface 144 relative to the upper surface 132 decreases with the change in the position of the contact surface 144. That is, the allowable variation in the absolute value of the tangent slope at any point on the contact surface 144 is related to the position of that point on the contact surface 144.

[0094] Here, the change conforms to .

[0095] Where n1 is the refractive index of the refractive structure 140b, and n2 is the refractive index of the light-transmitting structure 150. dK is the critical angle for total internal reflection when light enters the light-transmitting structure 150 from the refractive structure 140b. L is the path length between the incident position on the contact surface 144 and the upper surface 132 when light enters the contact surface 144 from the peripheral region 136 and undergoes total internal reflection. dK is the amount by which the slope of each point (i.e., position dL on the path length L) decreases as the path length L increases. The larger the path length L corresponding to each position dL is, the smaller the allowable amount of slope decrease at that position dL is.

[0096] More specifically, K refers to the total change in slope from the upper surface 132 to the light incident point on the contact surface 144, which is the sum of the integrals of all dK quantities from the upper surface 132 along the contact surface 144 to the light incident point.

[0097] The above formula means that when the path length (L) between the incident position on the contact surface 144 and the upper surface 132 is known, the landing point of the reflected light must also be known. dK / dL represents the upper limit of the slope that continues to decrease at the landing point.

[0098] In other words, when the refractive index (n1) of the refractive structure 140b is greater than the refractive index (n2) of the light-transmitting structure 150, as the path length (L) between the incident position on the contact surface 144 and the upper surface 132 increases, the decrease in slope (K) of the contact surface 144 will slow down. When the decrease in slope (K) is less than or equal to the above formula, the light guiding state in which the light undergoes total internal reflection within the refractive structure 140b can continue to occur.

[0099] Figure 5 This is a partial cross-sectional schematic diagram of a display panel according to another embodiment of the present invention. Please refer to... Figure 5 In this embodiment, the micro light-emitting component 130 of the display panel 100c has a light-emitting layer 138, and on the longitudinal section of the micro light-emitting component 130, the central axis X1 of the micro light-emitting component 130 in the direction perpendicular to the display substrate 110 (vertical direction) and the central axis X2 of the light-emitting layer 138 in the direction perpendicular to the display substrate 110 do not coincide with each other.

[0100] Figure 5 The display panel 100c and Figure 2A The main difference between the display panel 100 and the other panel is that... Figure 2A In the process, the central axis X3 of the central region 134 of the micro light-emitting component 130 is located between the central axis X1 of the micro light-emitting component 130 and the central axis X2 of the light-emitting layer 138.

[0101] In this embodiment, the central axis X3 of the central region 134 of the micro light-emitting component 130 coincides with the central axis X2 of the light-emitting layer 138. In this way, the central axis X3 of the central region 134 can be shifted to the central axis X2 of the light-emitting layer 138, further modifying the light pattern of the micro light-emitting component 130 and making the light pattern symmetrical.

[0102] In summary, the notch design of the refractive structure in the display panel of the present invention ensures that light emitted from the central region of the micro-light-emitting components with a small divergence angle will not enter the refractive structure, thus avoiding the problem of light with a small divergence angle being refracted and diverged by the refractive structure. Furthermore, this configuration allows light with a large divergence angle in the central region to enter the refractive structure, where it undergoes secondary refraction before reaching the reflective structure. This reduces the height at which the light is incident on the reflective structure, thereby reducing the need for the reflective structure. Additionally, the light reflected by the reflective structure can be directed towards the front of the micro-light-emitting components, improving light extraction efficiency. Because the light extraction efficiency of each micro-light-emitting component in the display panel is effectively improved, the light extraction uniformity of the display panel is increased.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A display panel, characterized in that, Include: Display substrate; A reflective structure is disposed on the display substrate, and the reflective structure divides the surface of the display substrate into multiple pixel areas; A plurality of micro-light-emitting components are disposed in one of the plurality of pixel regions, and each micro-light-emitting component has an upper surface on the side away from the display substrate, the upper surface defining a central region and a peripheral region surrounding the central region; Multiple refractive structures, each of the refractive structures covering the peripheral region of one of the multiple micro-light-emitting components and exposing the central region of the micro-light-emitting component therein to form a notch; as well as A light-transmitting structure covers the plurality of refractive structures and the plurality of micro-light-emitting components. The light-transmitting structure fills each of the recesses and contacts each of the central regions. The refractive index of the light-transmitting structure is less than that of the refractive structure. Each of the refractive structures has a contact surface that contacts the light-transmitting structure on the side away from the corresponding peripheral region, and each contact surface forms an acute angle with the upper surface of the corresponding micro-light-emitting component.

2. The display panel according to claim 1, characterized in that, The reflective structure has a reflective wall on one side adjacent to each of the micro-light-emitting components, the reflective wall comprising: The lower layer is connected to the display substrate; The upper layer is connected to the lower layer, and the absolute value of the slope of the upper layer relative to the upper surface is less than the absolute value of the slope of the lower layer relative to the upper surface.

3. The display panel according to claim 1, characterized in that, The plurality of refractive structures are respectively filled between the corresponding micro-light-emitting components and the reflective structures, and between the micro-light-emitting components and the display substrate.

4. The display panel according to claim 1, characterized in that, The edges of the contact surfaces of each of the refractive structures are connected to the reflective structure, and each of the refractive structures has a top away from the corresponding upper surface. In the direction of the top toward the reflective structure, each of the contact surfaces includes a continuous curved surface, a plurality of curved surfaces with different curvature centers, or a plurality of inclined surfaces with different slopes.

5. The display panel according to claim 4, characterized in that, The absolute value of the tangent slope of each of the contact surfaces relative to each of the upper surfaces increases from the side adjacent to the notch toward the side adjacent to the reflective structure.

6. The display panel according to claim 4, characterized in that, On the longitudinal section of the plurality of micro light-emitting components, a portion of the light-transmitting structure is disposed between the plurality of contact surfaces and the reflective structure.

7. The display panel according to claim 4, characterized in that, On the longitudinal section of the plurality of micro light-emitting components, the connection point between each contact surface and the reflective structure is flush with the upper surface of the corresponding micro light-emitting component, or located on the side of the upper surface away from the display substrate.

8. The display panel according to claim 1, characterized in that, Each of the refractive structures has a top located away from the plurality of upper surfaces and an inner sidewall connecting the corresponding upper surface, each of the inner sidewalls comprising at least a plane, a curved surface, or a combination thereof.

9. The display panel according to claim 8, characterized in that, In the direction from each of the tops toward the corresponding upper surface, the absolute value of the tangent slope of each of the inner sidewalls relative to the respective upper surface increases from the top toward the upper surface.

10. The display panel according to claim 1, characterized in that, The peripheral area covered by each of the aforementioned refractive structures accounts for more than 50% of the area of ​​the upper surface.

11. The display panel according to claim 1, characterized in that, Each of the refractive structures covers a portion of the surface of the reflective structure, and the thickness of the plurality of refractive structures in the direction perpendicular to the display substrate increases from the side adjacent to the notch toward the side adjacent to the reflective structure.

12. The display panel according to claim 11, characterized in that, The absolute value of the tangent slope of each of the contact surfaces relative to each of the upper surfaces decreases from the side adjacent to the notch toward the side adjacent to the reflective structure.

13. The display panel according to claim 12, characterized in that, The absolute value of the slope of the tangent to each of the contact surfaces relative to each of the upper surfaces varies by an amount, the amount of variation conforming to Where n1 is the refractive index of the refractive structure and n2 is the refractive index of the light-transmitting structure. Let d be the critical angle for total internal reflection when light enters the light-transmitting structure from the refractive structure; L is the path length between the incident position dL on the contact surface and the upper surface when light enters the contact surface from the peripheral region and undergoes total internal reflection; and dK is the amount by which the slope of the contact surface at position dL decreases as the path length L increases.

14. The display panel according to claim 1, characterized in that, Each of the micro-light-emitting components has a light-emitting layer, and on the longitudinal section of each micro-light-emitting component, the central axis of the micro-light-emitting component along the direction perpendicular to the display substrate does not coincide with the central axis of the light-emitting layer along the direction perpendicular to the display substrate.

15. The display panel according to claim 14, characterized in that, The central axis of the central region of the micro-light-emitting component is located between the central axis of the micro-light-emitting component and the central axis of the light-emitting layer, or the central axis of the central region of the micro-light-emitting component coincides with the central axis of the light-emitting layer.

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